1. Field of the Invention
The present invention generally relates to an organic waste water treating apparatus for treating waste water which contains organic material, such as crushed solid organic material, or waste water obtained by primary treating of such waste water.
2. Description of the Related Art
Conventionally, waste discharged from homes, including food waste, bottles, and the like, is collected separately and burnt at an incinerator. With this method, however, a problem arises in that a large amount of manpower is required to carry, collect, and treat the waste. In addition, burning is not desirable in light of recycling of resources and preservation of natural environments.
As a means for crushing food waste, a disposal unit is conventionally known. Crushing waste in a disposal unit and discharging the crushed waste with water is very convenient because the user of the disposal unit does not need to laboriously collect the waste. However, this causes a problem in that it may increase solid content and organic concentration in waste water, which may clog a sewage pipe and therefore impose a larger treating burden on a sewage treatment plant.
In light of the above, an apparatus has been proposed for treating crushed-organic-waste-containing waste water at home or in an apartment house. By using this apparatus, organic waste can be disposed of at respective homes without causing adverse effects on a sewage pipe and relevant equipment.
Such an apparatus is disclosed by, for instance, Japanese Patent Laid-open No. Hei 9-1117. In this apparatus, crushed-organic-waste-containing waste water is supplied to a solid treating section so that crushed waste is removed from the water through decomposition before being supplied to a waste water treating tank for aeration. With this arrangement, waste water which contains organic waste crushed by a disposal unit can be treated by an aerobic biological process.
In this apparatus, wood chips or the like are filled in the solid treating section and stirred by a paddle. This is basically an identical structure to that of a conventional compost-making apparatus for treating general organic waste.
The apparatus has a problem in that water tends to remain in the solid treating section under some operating condition because crushed-organic-waste-containing waste water discharged from a disposal unit usually contains more water than general organic waste does. The residual water may cause an anaerobic condition inside the apparatus.
Further, the filling material may easily stick together to form a lump when stirred by a paddle under moist conditions. This may impair the water passing ability.
Furthermore, although the apparatus employs a method basically identical to the activated sludge method, in which waste water is exposed to aeration treating using an air diffuser held in a waste water treating tank and aerated water is discharged therefrom, the apparatus is not equipped with a tank sufficiently large to store sediment of aeration mixture liquid. Therefore, this apparatus may not be capable of performing adequate treating when aeration mixture liquid has high suspended solid concentration (MLSS: Mixed Liquor Suspended Solid).